1. Field of the Invention
The present invention relates to lighting apparatuses for use in indoor or outdoor installation places, which are adapted to be installed in wide spaces, such as offices or basement garages, or in elongated spaces, such as corridors or tunnels, or adapted to be used as streetlights or security lamps. More particularly, the present invention relates to lighting apparatuses, which provide preset minimum illumination upon sensing no object in order to relieve anxiety that people may feel when passing through a dark and long space, which provide efficiently bright illumination upon sensing an object through use of a complex sensor by efficiently controlling the brightness of a lamp based on movement of the object, and which provide illumination in consideration of physiological reactions of humans with respect to the brightness of a lamp, thereby achieving an additional advantage of reduction in energy consumption.
2. Description of the Related Art
Current lighting apparatuses are configured to sense motion of people at night so that lighting apparatuses present at positions where motion of people is sensed are turned on and then turned off when people move out of a sensing range thereof.
A conventional lighting apparatus is comprised of a sensor unit consisting of a plurality of motion sensors each having a characteristic code, a single processor to process a signal from the sensor unit, a controller to control a lamp unit in response to the signal from the signal processor, and the lamp unit to drive a lamp located at any position in response to a control signal from the controller. With regard to the lighting apparatus installed in any area, through use of the motion sensors to sense whether a person who requires illumination is present, the corresponding lighting apparatus is turned on upon sensing the presence of the person and then turned off when the person moves out of the corresponding area. Then, another lighting apparatus, which is installed in an area where the person is newly sensed, is turned on.
In use of the conventional lighting apparatus as described above, in the case in which a person moves out of a particular sensing area, but is not immediately sensed in a new sensing area, all lighting apparatuses temporarily become a power-off state, which may cause the person who passes through an elongated space to feel anxiety. In addition, note that the sensors of the lighting apparatus do not immediately sense an object, such as a person, car, or the like, when the object initially enters a particular space. Thus, the person who suddenly enters a dark space is liable to feel anxiety. In addition, since a lighting apparatus, installed in an area where a person is sensed, is turned on, but other lighting apparatuses installed in other areas are in a power-off state and, thus, only a particular area is illuminated and the other areas are in a dark state, a person who passes through a wide and long space cannot know whether any dangerous object is present in a dark area and thus may feel anxiety and be exposed to danger of accidents.
There is also proposed a method for installing a plurality of lighting apparatuses, rather than a single product, so that the lighting apparatuses interwork with one another in a wired or wireless manner. However, executing interworking of the lighting apparatuses in a wired manner requires installation of cables, causing inconvenient construction and high construction costs. On the other hand, executing interworking of the lighting apparatuses in a wireless manner is likely to cause communication errors under the influence of a surrounding environment and requires a complicated configuration including a communication unit, and the like.